Forty-five growing V-line rabbits of both sexes, 5 weeks old, were used for the study through summer season from July to September. The rabbits were randomly allocated to five treatments groups of 9 rabbits each. Each treatment was further sub-divided into 3 replicate of 3 rabbits. Group one fed control diet free of feed additives and served as a control. Group 2 and 3 supplemented with 100 and 200 mg allicin / kg diet. Group 4 and 5 supplemented with 100 and 200 mg lycopene / kg diet, respectively. Results showed that the groups fed allicin 200 mg/kg and lycopene100 mg/kg in their diets recorded the best (P ≤ 0.05) significant average daily weight gain as compared with the control group. The other experimental groups were numerically best in comparison with the control group. Significant improvement in feed conversion ratio was recorded in all experimental groups in comparison with control. Carcass traits and hematological parameters were insignificantly affected by different treatments. All feed additives used in the present study significantly increased antibody titters against SRBCs compared with control group at 7, 14 and 21 days after vaccination. Serum total lipids was significantly (P ≤ 0.05) decreased due to addition of different feed additives, except with 200 mg allicin in the diet serum total lipids was equal to the control group. Blood serum total cholesterol and triglycerides were significantly (P ≤ 0.05) reduced by feeding diets containing different levels of allicin or lycopene in comparison with the control group. The results showed that low density lipoprotein was numerically decreased, however, high density lipoprotein and HDL/LDL ratio were numerically increased due to inclusion different feed additives in the diets. Exposing growing rabbits to high temperature conditions during summer season resulted in elevated (P ≤ 0.05) serum MDA, while serum total antioxidant capacity was decreased as presented in the control group, however, supplementation of allicin and lycopene appeared to antagonize the effect of high temperature. In conclusion, rabbit dietary supplementation with allicin or lycopene could have beneficial effects on performance under summer environment without any side effects.